(a) Field of the Invention
This invention relates to crushing apparatus.
The apparatus of the present invention is useful for crushing rock, and will be described with particular reference to this application. However, the apparatus also is useful for crushing other materials (e.g. glass, minerals, bricks, grains).
(b) Background of the Invention
Crushing at present is carried out in a number of types of apparatus:- ball mills, rod mills, hammer mills and jaw crushers. However, for `accurate` crushing i.e. crushing material to obtain particles within a narrow size range, and with relatively few fines, a jaw crusher commonly is used. A jaw crusher crushes by a hammer-and-anvil type of action: a moving jaw is swung against a stationary jaw. The position of the stationary jaw can be adjusted to alter the minimum gap between the jaws. This type of crusher gives good results, but is rather wasteful of power because a great deal of the force of the moving jaw is absorbed by the stationary jaw rather than by the material being crushed. In consequence, the apparatus requires a heavy support, to endure the uneven load on the apparatus imposed by the impacts on the stationary jaw. Such a jaw crusher is shown and described in Australian Pat. No. 227301.